maybe wrong place to post but really need help about my simple pc

proc : Intel Celeron Dual Core 2.5ghz fsb 800
ram : Kingston DDR2 800 2gb
mobo : Asrock G31-MS

the problem is, just like the mobo won't detect the ram as 800mhz, I only got 667 when i check on mybios. FYI this mobo got boot failure guard if anycase it doesn't stable.

Sorry for asking it here, hope could helping